The first baby with three biological parents could be conceived next year after the Government announced a major review of Britain’s fertility laws.

The move would allow doctors to use a revolutionary IVF technique that prevents incurable, deadly genetic illnesses being passed down from mothers to their children.

Babies created with the therapy – called three-parent IVF – would inherit 98 per cent of their DNA from their ‘real’ parents. The rest would come from a female donor.

The scientists say the donor genes would not alter the children’s appearance or personality, but would stop them dying from painful diseases of the heart, liver and brain.

But the revelation has horrified embryo campaigners who accused doctors of ‘meddling around with the delicate building blocks of life’.

It also raises questions about parental rights and whether the donor parent would have any say in the upbringing of a child.

Health Secretary Andrew Lansley has asked the fertility watchdog, the Human Fertilisation and Embryology Authority, to investigate the safety of the technique. If MPs back the change, it could be introduced in 12 months.

The new therapy, designed by Professor Doug Turnbull, of Newcastle University, centres on mitochondria – the power packs inside cells that convert food into energy.

Each mitochondrion contains a small amount of DNA. Around 100 babies every year are born with a disease caused by faulty mitochondrial DNA. There is no cure and many die within hours of birth.

Unlike the bulk of the DNA in the human body – which comes from both parents – mitochondrial DNA is only passed down from mothers.The new technique replaces faulty mitochondria with healthy transplants from a donor egg cell.

Professor Alison Murdoch, head of the Department of Reproductive Medicine at Newcastle University, said: ‘We are not ready to do this in patients now but the science is progressing very rapidly and we need to get Parliament to discuss this again. We anticipate that the review could take about a year. There is no guarantee that we will have all the evidence we need to secure a licence in a year but we need to anticipate that we may have.

‘As doctors we have a duty to treat disease and where possible to prevent disease. With diseases for which there are no treatments the imperative to develop new treatments is even greater. Of course no treatment is ever risk free and if there are risks we will need to quantify these so that doctors can discuss them with patients.’